a) Field of the invention
This invention relates to detergent compositions, each of which has a pearly luster and is excellent in the dispersion stability of a pearlant.
b) Description of the Related Art
In detergents such as shampoos, face washes and body washes, it has been the conventional practice to alter their appearances to have a pearly luster so that they can be provided with an additional commercial value.
Nowadays, a detergent composition with a pearly luster is primarily obtained by using a long-chain fatty acid glycol ester, which is in a solid form at room temperature, or the like as a pearlant, adding the pearlant at room temperature upon production of a detergent, heating the resulting mixture until the pearlant melts, and then cooling the heated mixture back to have the pearlant crystallized; or by mixing a thick dispersion, which has been obtained beforehand by melting the pearlant and cooling it back and has a pearly luster, with detergent ingredients at room temperature. Whichever method is used, the pearlant is dispersed as fine crystals in the final composition.
However, conventional detergent compositions, which have been obtained as described above and have a pearly luster, are not sufficient in terms of providing stability for the dispersed pearlant and, especially when stored for a long time, may undergo separation and develop precipitation in some instances.
An object of the present invention is to provide a detergent composition, which is excellent in the dispersion stability of a pearlant and has a long-lasting beautiful pearly luster.
The present inventors have found that use of a specific glyceryl ether along with a particular pearlant makes it possible to obtain a detergent composition, which is excellent in the dispersion stability of the pearlant and, even when stored over a long time, does not undergo separation and develop precipitation and has a long-lasting beautiful pearly luster.
The present invention, therefore, provides an aqueous liquid detergent composition comprising the following ingredients (A), (B) and (C):
(A) 1 to 50 wt. % of a surfactant selected from an anionic surfactant, a nonionic surfactant or an amphoteric surfactant;
(B) 0.3 to 5 wt. % of a long-chain fatty acid glycol ester represented by the following formula (1): 
xe2x80x83Wherein R1 represents a linear or branched, alkyl or alkenyl group having 13 to 23 carbon atoms, n stands for an integer of 1 to 3, and A represents a hydrogen atom or a group 
xe2x80x83in which R1 has the same meaning as defined above; and
(C) 0.1 to 10 wt. % of a glyceryl ether having one or more linear or branched, alkyl or alkenyl groups having 4 to 12 carbon atoms.
The detergent composition according to the present invention contains the pearlant in a stably dispersed form, has a beautiful pearly luster, and moreover, remains stable over a long time. The detergent composition, therefore, gives a sense of richness and a sense of warmth to users.
The surfactant employed as the ingredient (A) in the present invention is selected from an anionic surfactant, a nonionic surfactant or an amphoteric surfactant.
Preferred examples of the anionic surfactant can include sulfates, sulfonates and carboxylates. Illustrative are alkyl sulfates, polyoxyalkylene alkyl ether sulfates, polyoxy-alkylene alkenyl ether sulfates, alkyl sulfosuccinates, alkyl polyoxyalkylenesulfosuccinates, alkylbenzene sulfonates, xcex1-olefinsulfonates, polyoxyalkylene alkyl phenyl ether sulfates, glyceride sulfates, amideether sulfates, higher fatty acid salts, alkanesulfonates, and xcex1-sulfofatty acid ester salts.
Among these anionic surfactants, alkyl sulfates, polyoxyalkylene alkyl ether sulfates and polyoxyalkylene alkenyl ether sulfates are particularly preferred. More preferred are alkyl sulfates represented by the following formula (2) and also, polyoxyalkylene alkyl ether sulfates and polyoxyalkylene alkenyl ether sulfates represented by the following formula (3):
R2OSO3Mxe2x80x83xe2x80x83(2)
R3O(CH2CH2O)mSO3Mxe2x80x83xe2x80x83(3)
wherein R2 represents an alkyl group having 10 to 18 carbon atoms, R3 represents an alkyl or alkenyl group having 10 to 18 carbon atoms, M represents an alkali metal atom, an alkaline earth metal atom, an ammonium ion, an alkanol amine residue or a basic amino acid residue, and m stands for an integer of from 1 to 5 in terms of weight average.
Examples of the nonionic surfactant can include polyoxyalkylenealkyl ethers, polyoxyalkylene fatty acidesters, polyoxyalkylene sorbitan fatty acid esters, polyoxyalkylene sorbitol fatty acid esters, polyoxyalkylene glycerin fatty acid esters, monoglycerides, sorbitan fatty acids, fatty acid alkanolamides (fatty acid monoethanolamides, fatty acid diethanolamides, and the like), and alkyl polyglycosides. Of these, fatty alkanolamides and polyoxyalkylene alkyl ethers are particularly preferred.
Examples of the amphoteric surfactant can include fatty acid amidopropyl betaines, betaine acetates, betaine amidoacetates, sulfobetaines, amidosulfobetaines, phosphobetaines, alkylamine oxides, and amidoamineoxides. Of these, fatty acid amidopropyl betaines are particularly preferred.
As the ingredient (A) in the present invention, it is preferred to combine an anionic surfactant with a nonionic surfactant and/or an amphoteric surfactant. It is more preferred to combine such that an anionic surfactant and a fatty acid amidopropyl betaine, fatty acid alkanolamide or polyoxyalkylene alkyl ether are included.
As the ingredient (A), one or more surfactants can be used. The ingredient (A) amount to 1 to 50 wt. %, preferably 10 to 50 wt. %, notably 10 to 22 wt. of the whole composition. This range is preferred as good cleansing power is available.
As the ingredient (B), i.e., the long-chain glycol ester (1) for use in the present invention, an ester of the formula (1) in which R1 is an alkyl group having 13 to 23 carbon atoms, especially an alkyl group having 18 carbon atoms is preferred. Illustrative are ethylene glycol monostearate, ethylene glycol monopalmitate, ethylene glycol distearate, ethylene glycol dibehenate, diethylene glycol monostearate, diethylene glycol monopalmitate, diethylene glycol distearate, and triethylene glycol monostearate.
Particularly preferred as the ingredient (B) is ethylene glycol distearate.
One or more long-chain fatty acid glycol esters (1) can be used as the ingredient (B). The ingredient (B) amounts to 0.3 to 5 wt. %, preferably 0.5 to 5 wt. %, notably 0.8 to 3 wt. % of the whole composition. This range is preferred because a beautiful pearly luster and good stability are available.
The glyceryl ether as the ingredient (C) contains one or more linear or branched, alkyl or alkenyl groups having 4 to 12 carbon atoms. Preferred examples can include glyceryl ethers containing one or more alkyl groups having 4 to 12 carbon atoms, such as n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, isononyl, n-decyl and/or n-lauryl groups. Particularly preferred are glyceryl ethers containing one or two alkyl groups, especially one alkyl group having 4 to 11 carbon atoms, more preferably 6 to 11 carbon atoms, notably 8 carbon atoms.
As the ingredient (C), one or more glyceryl ethers can be used. The ingredient (C) amounts to 0.1 to 10 wt. %, preferably 0.5 to 5 wt. %, notably 1 to 5 wt. % of the whole composition. This range is preferred because a beautiful pearly luster and good stability are available.
The detergent composition according to the present invention may further contain a silicone, and the resulting detergent composition can bring about excellent conditioning effect. It has been difficult to have a silicone stably contained in conventional aqueous liquid detergent compositions. In the present invention, however, the inclusion of the glyceryl ether as ingredient (C) has made it possible to stably disperse a silicone.
Examples of the silicone can include:
(1) Dimethylpolysiloxanes represented by the following formula:
(Me3)SiOxe2x80x94(Me2SiO)nxe2x80x94Si(Me3)
wherein Me represents a methyl group and n stands for a number of from 3 to 20,000.
(2) Amino-modified silicones:
Although a variety of amino-modified silicones are usable, particularly preferred is the amino-modified silicone described under the name of xe2x80x9cAmodimethiconexe2x80x9d in xe2x80x9cInternational Cosmetic Ingredient Dictionary and Handbookxe2x80x9d, Third Edition, published by The Cosmetic, Toiletry, and Fragrance Association (CTFA), U.S.A. This amino-modified silicone may preferably be used in the form of an aqueous emulsion, and its commercial products can include, for example, xe2x80x9cSM 8704Cxe2x80x9d (trade name, product of Toray Silicone Co., Ltd.) and xe2x80x9cDC 929xe2x80x9d (trade name, product of Dow Corning Corp.).
(3) Further, polyether-modified silicones, methyl-phenylpolysiloxane, fatty-acid-modified silicones, alcohol-modified silicones, alkoxy-modified silicones, epoxy-modified silicones, fluorine-modified silicones, cyclic silicones, alkyl-modified silicones.
Among these, dimethylpolysiloxane is particularly preferred.
These silicones may be used either singly or in combination, and may amount to 0.2 to 5 wt. %, especially 0.5 to 2 wt. % of the whole composition.
The detergent composition according to the present invention may further contain a cationic polymer, and the resulting detergent composition can bring about superb conditioning effect. Examples of the cationic polymer can include cationized cellulose derivatives, cationic starch, cationic guar gum derivatives, homopolymer of diallyl quaternary ammonium salt, diallyl quaternary ammonium salt/acrylamide copolymer, quaternized polyvinylpyrrolidone derivatives, polyglycol polyamine condensation products, vinylimidazolium trichloride/vinylpyrrolidone copolymer, hydroxyethylcellulose/dimethyldiallylammonium chloride copolymer, vinylpyrrolidone/quaternized dimethylaminoethyl methacrylate copolymer, polyvinylpyrrolidone/alkyl amino-acrylate copolymer, polyvinylpyrrolidone/alkyl amino-acrylate/vinyl caprolactam copolymer, vinylpyrrolidone/methacrylamidopropyl chlorotrimethylammonium copolymer, alkyl acrylamide/acrylate/alkylaminoalkyl acrylamide/polyethylene glycol methacrylate copolymers, adipic acid/dimethylaminohydroxypropyl ethylenetriamine copolymer (xe2x80x9cCartaretinxe2x80x9d, trademark; product of Sandoz Chemicals Corp., U.S.A.), and cationic polymers disclosed in JP 53-139734 or JP60-36407. Of these, cationic cellulose derivatives are particularly preferred.
These cationic polymers may be used either singly or in combination, and may preferably amount to 0.01 to 5 wt. %, especially 0.05 to 1.5 wt. %, notably 0.1 to 0.8 wt. % of the whole composition. It is particularly preferred to use a silicone and a cationic polymer in combination in proportions of from 0.1 to 5 wt. %, respectively.
The detergent composition according to the present invention is in the form of an aqueous liquid making use of water as a medium, and may additionally contain one or more of ingredients used in general detergent compositions, for example, humectants such as propylene, glycerin, diethylene glycol monoethyl ether, sorbitol, and panthenol; colorants such as dyes and pigments; viscosity controlling agents such as methylcellulose, polyethylene glycol, and ethanol; pH regulators such as citric acid and potassium hydroxide; and salts such as sodium chloride, plant extracts, preservatives, disinfectants, chelating agents, vitamins, anti-inflammatories, anti-dandruff agents, fragrances, dyestuff, ultraviolet absorbers, antioxidants, and so on.
The detergent composition according to the present invention can be produced in a method known per se in the art, and can be formulated, for example, into body cleansing detergent preparations such as shampoos, body washes, face washes and hand washes.